Comparative Study to the Solar Photo-Fenton, Solar Photocatalyst of TiO2 and Solar Photocatalyst of TiO2 Combined with Fenton Process to Treat Petroleum Wastewater by RSM

Abstract

The present study is conducted to compare the performance of different oxidation processes such as the solar photo-Fenton, the solar photocatalyst of TiO 2 and solar photocatalyst of TiO 2 /Fenton process for the treatment of petroleum wastewater from Sohar oil refinery (SOR) by a central composite design (CCD) with response surface methodology (RSM). The degradation efficiency is evaluated in terms of chemical oxygen demand (COD) and total organic carbon (TOC) reductions. The solar photocatalyst of TiO 2 /Fenton method improved the performance of photocatalyst TiO 2 in the normal value of pH (7) for petroleum wastewater, therefore no need to adjust pH during this treatment. In acidic conditions pH <7, the solar photo-Fenton process is more efficient than the solar photocatalyst of TiO 2 process, while it is less efficient than the solar photocatalyst of TiO 2 process in alkaline conditions pH >7. The TiO 2 dosage and pH are the two main factors that improved the TOC and COD removal in the solar photocatalyst of TiO 2 /Fenton and the solar photocatalyst of TiO 2 processes while the pH and H 2 O 2 concentration are the two main factors in the solar photo-Fenton process.